Hole saws are typically used to cut large diameter holes in materials such as wood and metal and are usually mounted by means of an arbor to a drill press or other power tool. During a cutting operation, these saws generate high levels of vibration and are prone to rocking back and forth on the arbor, an effect known to those skilled in the art as wobble. This effect causes premature wear in the saw and diminishes its cutting accuracy and efficiency.
To counter these effects, prior art arbors incorporate a fixed position flange and drive pin arrangement. The hole saw characteristically includes a cylindrical body portion defining a cutting edge at one end. The opposite end of the body portion is closed by a drive plate. A threaded bore at the center of the drive plate mates with a lower threaded shaft portion on the arbor. The saw is threaded onto the arbor until it abuts the aforementioned fixed position flange. The drive pins pass through holes in the flange and engage mating holes in the drive plate. The flange and the drive pins coact to support the hole saw during a sawing operation. However, it is often difficult or impossible to both align the drive pins with the holes in the drive plate and have the drive plate abut the fixed position flange. Generally, the saw must be backed off from the flange until the holes in both the saw and flange are aligned. This causes a gap to be created between the saw and the flange thereby preventing the drive plate from being supported by the fixed position flange. The presence of the gap allows the saw to wobble during a sawing operation. This problem is exacerbated as the saw and its mounting threads wear.
Based on the foregoing, it is the general object of the present invention to provide an arbor for supporting a saw that attenuates vibration and wobble while obviating the previously described alignment problems.